This Small Business Innovation Research Phase I application describes how oligonucleotide microarray slides and services will be provided for researchers using Xenopus, a model system that has contributed tremendously to biology. Many research groups have little or no means for obtaining libraries for genomics studies and prominent among them are researchers who work with amphibians. To fulfill this need, we propose to generate oligonucleotide libraries representing genes from Xenopus laevis and X. tropicalis. Studies will be carried out to compare the global genomic expression profiles of X. laevis and X. tropicalis. The proposed work will allow Xenopus researchers to integrate the data from the historically significant X. laevis system with the relatively new X. tropicalis system, which offers the singular feature for the Xenopus system to carry out genetics and related studies. The efficacy of the proposed work will be carried out by comparing gene expression levels of selected genes from the microarray studies to levels determined from previous work and/or by conventional methods. The proposed research provides the basis for Phase II, which is to extend and develop the microarray products and services for X. laevis and X. tropicalis as well as other important and overlooked model systems. The proposed work will promote genomics and exploit lucrative commercial and academic markets.